It is practiced that an HMD (Head-Mounted Display) unit connected to a game machine is mounted on the head of a user to allow the user to operate a controller or the like to play a game while viewing a screen image displayed on the head-mounted display unit. In an ordinary stationary type display unit connected to a game machine, the visual field range of the user spreads also to the outer side of a screen image of the display unit, and therefore, the user may not concentrate on the screen image of the display unit or sometimes lacks in immersive experience in the game. In this regard, where a head-mounted display unit is mounted on a user, since the user does not view any other than a video displayed on the head-mounted display unit, there is an effect that the immersive experience in the video world is enhanced and the entertainment value of the game is enhanced further.
Further, if a panorama image is displayed on a head-mounted display unit such that, if a user who wears the head-mounted display unit rotates the head, then a panorama image or a virtual space over 360 degrees is displayed, then the immersive experience in the video is further enhanced and also the operability of an application such as a game is improved.